This disclosure relates to a scroll type device and more particularly to spinning or co-rotating scroll devices that are capable of operating at high speeds, but yet are small of structure.
Scroll devices have been used as compressors, pumps, vacuum pumps, and expanders for many years. In general, they have been limited to a single stage of compression due to the complexity of two or more stages. In a single stage, a spiral involute or scroll upon a rotating plate orbits within a fixed spiral or scroll upon a stationary plate. A motor shaft turns a shaft that orbits a scroll eccentrically within a fixed scroll. The eccentric orbit forces a gas through and out of the fixed scroll thus creating a vacuum in a container in communication with the fixed scroll. An expander operates with the same principle only turning the scrolls in reverse. When referring to compressors, it is understood that a vacuum pump can be substituted for the compressor and that an expander can be an alternate usage when the scrolls operate in reverse from an expanding gas.
Scroll type compressors and vacuum pumps of the orbiting type have also been used for many years. Orbiting type scroll compressors are typically limited in their maximum speed to under 4000 rpm (revolutions per minute) due to the unbalanced centrifugal forces that must be contained by bearings. This relatively low speed results in relatively large scroll devices. Higher speed scrolls that are also smaller and lighter weight are desirable for some applications. For example, having a small, lightweight, high speed scroll would be advantageous in aerospace applications and for portable medical equipment.
The present disclosure overcomes the limitations of the prior art where a need exists for higher speed equipment of compact form. The present disclosure provides a co-rotating scroll that can operate at high speeds such as 6000 rpm and higher.